Tongs



Sept. 26, 1961 .1. R. ANDERSON TONGS 5 Sheets-Sheet 1 Filed Sept. 23,1957 m .llw Urlil v Q q Q Q g 3 "u wh x L mm mm 86 v R ow ow 3 mm R km8w Q Q .(sm b- NM Q Q Q .9 o

INVENTOR John R. Anderson 5/ /-//.s' A7'7OPNEKS Sept. 26, 1961 J. R.ANDERSON 3,001,812

TONGS Filed Sept. 23, 1957 5 Sheets-Sheet 2 INVENTOR John R. An derson5) HAS ,dffOPA/EYJ,

Sept. 26, 1961 .1. R. ANDERSON TONGS 3 Sheets-Sheet 5 Filed Sept. 25,1957 INVENTOR John R. Anderson 5/ HA? ATTOPNEyS, W W

United States Patent .3,001,812 TONGS John R. Anderson, Pittsburgh, Pa.,'assignor to Heppenstall Company, Pittsburgh, Pa., a corporation ofPennsylvania Filed Sept. 23, 1957, Ser. No. 685,595 7 Claims. (Cl.294-437) This invention relates to linkage tongs adapted to handle loadsof different sizes and shapes while said tongs maintain a relativelyconstant over-all height. More particularly, this invention pertains tosuch tongs constructed for motor operation and having unique features ofadjustability, ease of operation and arrangement of forces markedlydifferent from prior practices.

Different tongs of the general kind disclosed herein are described andclaimed in United States patent application Serial No. 521,178, filedJuly 11, 1-955, now Patent No. 2,857,193 owned by the'assignee of thepresent invention. The present invention includes features, amongothers, which enable relatively efficient power drives to be readilyused and operated from a distance remote from the tongs disclosedherein. Further, a relatively wider range of :the adjustability of liftarms of tongs disclosed herein and somewhat lower headroom areachievable, such being :of significant worth in many industrial plants.Still further, the .tongs of this invention employ new linkage elementswhich affect the diagram of forces in a manner to safeguard against anychange in the position of the tongs when carrying loads. And, inconstructions disclosed herein, the diiving forces may be relativelysmaller for a given work load and the driving coupling is apportionableto the service in which the ton-gs is to be used. By using a drycoupling, the risk of leakage or overheating of fluid is eliminated andby using a ball screw and nut in certain embodiments the efiiciency ofthe new construction in the course 1 of operation is materiallyenhanced. This invention also enables a tongs to be .constructed'withmultiple legs for the handling of loads of unusual length.

Other objects, features and advantages of this invention will beapparent from the following description and from the accompanyingdrawings, which are illustrative only, in which FIGURE 1 is a view ofone embodiment of a new tongs of this invention, for carrying coilsof'strip or other material, illustrated in front view and, almost fullyclosed condition;

FIGURE 2 is aside view of the embodiment shown in FIGURE 1 with thelinkage in open-condition;

FIGURE 3 is a front view of the embodiment shown in FIGURES .1 and 2with the linkage in open condi .tion;

FIGURE 4 is a view, .partly in section, taken along line IV-IV ofEIiGURE3;

FIGURE Sis a side view, partly in section, ofa modified embodiment ofthis invention in open condition;

FIGURE 6 is a view taken along line W-VI .ofFIG- 'URE 5;

FIGURE 7 is a view taken along line VIIVII of FIGURE 6;

FIGURE 8 is a view of .a further embodimentof this invention havingvmultiplelegs and utilizable to handle sheets or plates including thoseof larger size and FIGURE 9 is a front viewof the further embodimentillustrated in FIGURE 8.

.clevis space 12,:the upper endseof --which are joined by a spool vl3.adap-tedtobe engaged, for example, by the :hook of a .crane of other.materials handling item of equipment. -A platform 14 is affixed to theside of head 11 and adjustable relative thereto toward and away fromsaid head. A reversible electric motor 15 is fixed to platform 14 andadapted to drive belts 16 through a dry coupling 17, which may be one ofthe Flexidyne type, whenever motor 15 is energized. In such a Flexidynecoupling, the motor shaft spins a housing 18 having a predeterminedquantity of steel shot therein which effects coupling with a rotorhaving a shaft keyed to a driving pulley 19 for the belts 16. The lowerend of head 11 is drilled and fits around the top of a columnguide 20 towhich it is secured by keys 21. An opening 22 in the side of head 11enables the belt 16 to engage a driven pulley 23 fixed to the top of avertical threaded operating shaft 24. The threads on shaft 24 are shapedto cooperate with a ball bearing nut 25 of the Saginaw type with theresult that rotation of shaft 24 is performed in a relativelyfrictionless manner relative to its nut 25 and the power efiiciency ofthe new construction is correspondingly advanced.

Nut 25 is fixedly held by a crosshead 26 extending across the interiorof hollow column 20. Column 20 is rovided with slots 27 in registry,which slots are slidably engaged by runners 28 of the crosshead 25. Anupper yoke 29 surrounding column 20 is keyed to crosshead 26 by keys 30.The keys 30 also constitute the pivots for the linkage elements of thetongs 10. A lower frame or yoke member 31 is fastened to the bottom ofcolumn 20 by keys 32 which also serve as the central pivots for thelower end of such new linkage. A thrust bearing 33 is mounted in thelower end of column 20 and serves as a bearing for the lower stub shaftend of shaft 24, the screw thread and stub shaft parts of which areprovided with a coupling 34. A magnetic brake 35 is positioned at thelower end of shaft 24 within the sides of a depending work rest 36secured to yoke 31 and column 20. Brake 35 preferably is electricallyreleased and spring applied and in the circuit of motor 15 so that upon,energization of motor 15 brake 3511's released, and, vice versa.

The new linkage in tongs 10 is duplicated in mirror fashion on the frontside and on the back side. Further, the new linkage is symmetrical tothe left and right side, in mirror fashion, of the median longitudinalplane through the axis'of column 20 perpendicular to the plane of thepaper on which FIGURE 3 appears. The linkage elements to each side ofsuch median plane are suitably connected by longitudinally extendingspacers and bars to provide the desired rigidity of structure in thecourse of operation. Such linkage includes, on the front and back, apair of outwardly and downwardly extending main levers 37, the upperends of which are pivoted in registry about the axis of the pivots 30and the lower ends of which are pivoted to lift arms 38 at 39. Strutmembers 40 are upwardly and outwardly extending and are pivoted at theirlower ends in registry about the axis of the pivots 32. The upper endsof the respective struts 40 are pivoted at 41 to the levers 37. Eachstrut to each side and on the front and back comprises two parallelportions spaced by spacers 42 a distance sufficient to span theparticular lever 37 to which they are pivotally connected. The innerstrut element 40a in each such pair is provided with a projecting end4%. Such projecting ends 40b are pivotally connected by links 43 to theupper extension 380 of the lift arms 38. In this way, the forcesoperative upon tongs It in the course of carrying or handling a loadinhibit the tendency for the load to try to spring such arms apart by awedging action against the opposed load supporting steps 44 on oppositesides of the tongs. Further, such new linkage enables the lift arms 38to come closer to column 20, as indicated in FIGURE 1, Where the tongsis shown in almost fully closed position. Fully closed position wouldoccur when the arm plates 4-5 abut the sides 46 of rest 36. It should benoted too that the linkage elements are straight from the central pivotsthereof to the pivotal connections with the lift arms.

In operation, when a load of 47 is to be engaged, the tongs may beopened by rotating shaft 24 to drive yoke 29 toward yoke 31 until thetongs can be lowered to span the load, as shown in FIGURE 3, and, ifdesired, may be allowed to rest on the load to be supported in partthrough the engagement of rest 36 with the top of coil 47. Thereupon,the motor 15 is energized releasing brake 35 so as to turn shaft 24 in adirection which will raise yoke 29 on column 20 until the plates 45 comeagainst the ends of coil 47, whereupon motor 15 is deenergized and brake35 automatically reapplied so that upon the lifting of head 11, tongs 10will transport coil 47 to any location desired. In the closing movementof tongs 1t), moreover, even if motor 15 should not be shut off, thesetting of the Flexidyne coupling 17 can be made such that upon apredetermined overload the rotor therein will slip and stop turning thebelt 16 although it will continue to keep the closing pressure of thelift arms 38 against the load 47 and constitute a safe tongs even thoughthe brake 35 has not been reapplied because the power to motor 15 hasnot been shut off. After coil 47 is transported to its new location, thetongs 10 are opened and are then ready for a new materials handlingoperation.

A modified embodiment of this invention is illustrated in FIGURES to 7and parts thereof corresponding generally in construction andfunctioning to parts in the embodiment shown in FIGURES l to 4,inclusive, are marked with the same reference numerals with the additionof a prime accent thereto. In such modified embodiment of FIGURES 5 to7, a pair of longitudinally spaced columns 20 are provided so that shaft24' may be centrally positioned between such columns. Further, motor 15is mounted adjacent the lower portion of shaft 24 with a saving inheadroom, which is of importance in many industrial plants. Thecrosshead 26' in the case of the FIGURE 5 embodiment is fixed to andextends between the respective front and back parts of such yoke 29'.The coupling 34 is, however, made flexible in order to accommodate anytendency for the axis of the shaft to be subjected to bending forces inthe course of the operation of tongs Still further, provision is made inthe modified embodiment of FIGURES 5 to 7 for the counterweighting ofthe linkage and upper yoke 29', which upper yoke 29 is guided by bothcolumns 20' extending through spaced vertical openings in yoke 29'.Cables 43 extend over respective pulley 49 pivotally mounted in head 11and are connected at their other ends to counterweights 50 within thehollow interior of the respective columns 20. The effective weight andthe steadiness of such counterweights 50 may be increased by springs 51in compression and extending between the tops of the interiors of thecolumns 20 and the upper portions of the counterweights 50, as shown inFIGURE 5. The linkage of the modified embodiment of FIGURES 5 to 7 andthe operation thereof is essentially the same as that hereinabovedescribed in connection with the embodiment of FIGURES l to 4.

By means of this invention, a multi-legged tongs may be provided asillustrated by the further embodiment 52 of FIGURES 8 and 9 suitable forthe handling and lifting of strips, sheets and plates including those ofrelatively long and wide character. Such further embodiment 52 is also atongs of relatively lower headroom and the application of its grippingupon a load to be carried is uniform and effective. It employs theunique linkage hereinabove described in connection with the priorembodiments set forth in this application. In tongs 52, a longitudinallyextending upper box beam 53 and a longitudinally extending lower boxbeam 54 are provided in vertical registry. Main columns 55 at the frontand back ends extend between such beams and are rigidly connectedthereto. Auxiliary columns 56 are provided between the columns 55 andthe columns 56 are also rigidly connected top and bottom to the beams 53and 54 re spectively. A clevis 57 is afiixed centrally to the upperportion of beam 53 and straps 58 may extend from clevis 57 to therespective ends of beam 53 to aid in load support distribution when aloaded tongs 52 is being moved. Main sleeves 59 are adapted to travel upand down in horizontal and vertical registry with one another on therespective columns 55, as are the auxiliary sleeves 60 on the respectiveauxiliary columns 56.

As shown in FIGURE 9, an outwardly facing set of links 62 to each sideis provided in pivotal connection between the sleeves 59 whichcorrespond to the movable upper yoke of the previously describedembodiments and the fixed members 61 at the ends of beam 54. Members 61in turn correspond to the lower yoke members previously described inconnection with the other illustrated embodiments. Inwardly facing setsof links 63 are connected between upper yoke members in the form ofauxiliary sleeves 60 and lower yoke members 64 connected to the bottomof columns 56 and beam 54 as shown. The respective linkages at each ofthe columns are in horizontal registry as shown in FIGURE 9 and operatetogether when tongs 52 is operated.

The lift arms 65 to each side of the tongs 52 comprise a latticestructural frame having a load supporting step and lip 66 extendingforthe full length of the tongs and projecting beyond the ends thereof inthe illustrated further embodiment. Such lattice is longitudinally boundtogether at the top, also on each side, by an angle 73 and in likemanner a spacing bar 74 is provided along the axis of the pivot betweenthe connecting links 75 and the extensions 76 of the lift arms 65 toeach side of tongs 52. The headroom of tongs 52 may be made lower bymounting the power operator on an adjustable height platform 67 on beam54 and between the columns 56. Such power operator may comprise anelectric motor 68 having a Flexidyne coupling 69 to a speed reducer 70and a drive sprocket 71. A magnetic brake 72 is also mounted on platform67 and operate upon the rotor or driven shaft of the Flexidyne coupling.In that way the motor can come up to speed with relatively light loadingand when the power is cut off, the motor can lose speed and deceleratein a normal manner since the spring applied brake of brake mechanism 72is on the driven side of such coupling.

A longitudinal shaft 77 is mounted in pillow block bearings 78 withinthe interior of box beam 54. A driven sprocket 79 is driven by drivingsprocket 71 through a roller chain connection 80. Rotation of shaft 77by sprocket 79 will correspondingly rotate the sprockets 81 at therespective ends of shaft 77. Each of the sprockets 81 is in verticalalignment with an upper sprocket 82 pivotally mounted on a countershaftwithin upper beam 53. A roller chain 83 engages the respective sets ofsprockets 81 and 82 at each of the respective ends of tongs 52 with thefree ends of each chain being adjustably anchored in the lugs 84 and 85respectively on each of the sleeves 59. Hence, each sleeve 59 becomes alink to complete an endless chain 83 so that as the shaft 77 is rotatedin counterclockwise direction, as viewed in FIGURE 9, the uppersprockets 82 will also be rotated in counterclockwise direction and thesleeves 59 will be raised in synchronism. Such raising of the sleeves 59will raise the passive auxiliary sleeves 60 in synchronism therewithbecause of the linkage registry connections thereto respectively untilthe tongs has been closed to the desired extent upon a load or for otherpurpose. When the tongs 52 is in closed or partially closed condition,rotation of the shaft 77 in a clockwise direction will move the tongs inan opening direction. Such movement is occasioned by the energization ofmotor 68 and when such motor is energized, as described above, the brake72 is released until spring applied 'upon the de-energization of suchmotor. 'Beams 53 and54 are provided with appropriate openings for thepassage of the roller chains 83.

Various modifications may be made in aspects of the illustratedembodiment of my invention and in other embodiments without departingfrom the spirit thereof or the scope of the appended claims.

I claim:

1. In a tongs, apparatus comprising, in combination, a head, a guidecolumn connected to said head and extending below the same, an operatingshaft having ball receiving threads extending parallel to said column,an upper yoke movable by said shaft vertically along said column inguided relation thereto, a ball nut engaging said threads and connectedto said yoke to move it when said operating shaft is rotated, anelectric motor mounted on said tongs, a dry fluid flexible couplingconnected between said motor and said shaft, a magnetic brake on thedriven side of said coupling operatively connected to said shaft to holdit in unmovable position when said motor is de-energized, a lower yokemember connected to said column, symmetrical linkage extending to eachside of said tongs and pivotally connected at the upper and lowercentral portions thereof to said upper and lower yoke membersrespectively, two laterally downwardly and outwardly extending levers insaid linkage pivotally connected together at the upper ends thereof tothe center of said upper yoke, generally vertical lift arms pivotallyconnected to the lower portions of said levers respectively, strutmembers extending laterally outwardly and upwardly and pivotallyconnected at the lower ends thereof to the center of said lower yokemember, the upper ends of said struts being pivotally connected tothe-central portions of said levers respectively, said lift arms havingextensions above the pivotal connections with said levers respectively,said struts having projecting ends above the pivotal connections withsaid levers respectively, and links pivotally connecting saidprojections of said struts and said extensions on said lift armsrespectively, said links extending generally in the direction of saidlevers respectively.

2. In a tongs, apparatus comprising, in combination, a head, a guidecolumn connected to said head and extending below the same, an operatingshaft having threads extending parallel to said column, an upper yokemovable by said shaft vertically along said column in guided relationthereto, a nut engaging said threads and connected to said yoke to moveit when said operating shaft is rotated, an electric motor mounted onsaid tongs, a friction coupling connected between said motor and saidshaft and adapted to engage fully substantially at operating speeds ofsaid motor, a brake operatively connected to said shaft to hold it inunmovable position when said motor is de-energized, a lower yoke memberconnected to said column, symmetrical linkage extending to each side ofsaid tongs and pivotally connected at the upper and lower centralportions thereof to said upper and lower yoke members respectively, twolaterally downwardly and outwardly extending levers in said linkagepivotally connected together at the upper ends thereof to the center ofsaid upper yoke, generally vertical lift arms pivotally connected to thelower portions of said levers respectively, strut members extendinglaterally outwardly and upwardly and pivotally connected at the lowerends thereof to the center of said lower yoke member, the upper ends ofsaid struts being pivotally connected to the central portions of saidlevers respectively, said lift arms having extensions above the pivotalconnections with said levers respectively, said struts having projectingends above the pivotal connections with said levers respectively, andlinks pivotally connecting said projections of said struts and saidextensions on said lift arms respectively.

3, In a tongs, apparatus comprising, in combination,

arframe including a vertically extending column, a-screw shaft extendingparallel tosaid column, amotor mounted on said tongs in fixed relationto said column, a low starting torque and fast releasing couplingoperatively connected between said motor and said shaft, a brake on thedriven side of said coupling operatively connected to .saidtshaft tohold it unmoved when said motor is stopped, a sleeve member operativelyconnected to said shaft andtmovable up and down on said column by therotation of'said shaft, symmetrical linkage extending to each side ofsaid tongs and pivotally connected at the upper and lower centralportions thereof to said sleeve member 'and lower portion of said framerespectively, two laterallydownwardly and outwardly extending levers insaid linkage'pivotally connected at the upper portions thereof to saidsleeve, lift arms pivotally connected to the lower'portions of saidlevers respectively, two laterally upwardly and outwardly extendingstrut members pivotally connected at the lower portions thereof to saidframe below said sleeve, the upper portions of said strut members beingpivotally connected to intermediate potrions of said leversrespectively, said strut members having projecting ends extending abovethe pivotal connection with said levers respectively, said lift armshaving extensions extending above the pivotal connections with saidlevers respectively, and links pivotally connecting said projecting endsand said extensions respectively.

4. In a tongs, apparatus comprising, in combination, a plurality ofvertically extending horizontally aligned and spaced columns connectedtogether at the tops and bottoms thereof, sleeve mechanism extendingbetween said columns for guidance thereby and movable up and downthereon, a shaft operatively connected to said sleeve mechanism andadapted to be rotated to move said sleeve mechanism, sets of symmetricallinkage extending to .each side of a plane defined'by the axes of saidcolumns, said set of linkage being in horizontal alignment and connectedtogether for synchronous movement, laterally downwardly and outwardlyextending levers insaid linkage pivotally connected at the upper endsthereof'to said sleeve mechanism, .latera'lly'upwardly .and outwardlyextending struts pivotally connected at the lower ends thereof to thelower ends of said columns and pivotally connected at the upper endsthereof respectively to intermediate portions of said levers, liftmembers pivotally connected to the lower ends of said levers andextending downwardly therefrom, said struts having upwardly projectingends, said lift members having upwardly projecting extensions, andcompression links pivotally connecting the projecting ends of saidstruts and lift members above said levers to each side of said planerespectively.

5. In a tongs, apparatus comprising, in combination, a pair ofvertically extending horizontally spaced columns connected together atthe top and bottom thereof, a yoke member extending between said columnsfor guidance thereby and movable up and down thereon, a screw shaftpositioned between said columns, operatively connected to said yokemember and adapted to be rotated to move said yoke member, an electricmotor adjustably mounted and fixedly connected to the side of saidcolumns and adjacent the lower ends thereof and of said shaft,symmetrical linkage extending to each side of a plane defined by theaxes of said columns, laterally downwardly and outwardly extendinglevers in said linkage pivotally connected at the upper ends thereofabout a common axis to said yoke member, laterally upwardly andoutwardly extending struts pivotally connected at the lower ends thereofto the lower ends of said columns about a common axis and pivotallyconnected at the upper ends thereof respectively to intermediateportions of said levers, lift members pivotally connected to the lowerends of said levers and depending therefrom, said struts having upwardlyprojecting ends, said lift members having upwardly projectingextensions, and co pression links pivotally connecting the projectingends 7 of said struts and lift members above said levers to each side ofsaid plane respectively.

6. In a tongs, apparatus comprising, in combination, a plurality ofhorizontally aligned vertically extending guides, upper and lowerlongitudinally extending beams rigidly connected to the tops and bottomsof said guides respectively, slidable members on each of said guidesadapted to move up and down thereon in synchronism, downwardly andlaterally outwardly extending levers pivoted to each of said slidablemembers and extending to each side of said tongs respectively, upwardlyand lateral- 1y outwardly extending struts pivotally connected to saidlower beam adjacent the bottoms of said guides respectively andextending to each side of said tongs respectively, said struts havingtheir upper ends generally in the plane of and connected to the centralportion of said levers respectively, load carrying arms pivotallyconnected to the outer ends of said levers on each side of said tongs,all of said load carrying arms being rigidly horizontally connected oneach of said sides respectively, said struts and load carrying anmshaving portions projecting above their respective pivotal connectionswith said respective levers, and compression links extending generallyin the direction of the adjacent levers pivotally connecting saidprojections respectively, said levers, struts and links adjacent each ofsaid guides comprising a set of linkage, said sets of linkage being inhorizontal registry, a motor and brake assembly mounted on said lowerbeam adjacent the center thereof and in longitudinally extendingfashion, a longitudinally extending sprocket shaft mounted on said lowerbeam and adapted to be rotated in a predetermined direction by saidassembly when said motor is energized and to be held against movement bysaid brake when said motor is not energized, sprockets mounted in saidupper beam adjacent certain of said slidable members and in verticalregistry with said sprocket shaft, endless chains engaging saidsprockets in vertical registry respectively, said slidable membersadjacent to said chains comprising the closing links for said chainsrespectively, whereby when said sprocket shaft is rotated said loadcarrying arms will open and close without significant change in verticalposition in accordance with movements of said slidable members and saidregistering linkages.

7. In a tongs, apparatus comprising, in combination, at least onevertically extending column, sleeve mechanism guidedly connected to saidcolumn and relatively movable up and down thereon, drive meansoperatively connected between said column and sleeve mechanism for suchrelative movement, a set of symmetrical linkage extending at rightangles to a vertical plane passing through the axis of said column,laterally downwardly and outwardly extending levers in said linkagepivotally connected at the upper portion thereof to said sleevemechanism, laterally upwardly and outwardly extending struts pivotallyconnected at the lower portions thereof to the lower portion of saidcolumn and pivotally connected at the upper portions thereof tointermediate portions of said levers respectively, lift memberspivotally connected to the lower portions of said levers and extendingdownwardly therefrom, said struts having upwardly projecting portions,said lift members having upwardly projecting portions, and linkspivotally connecting the projecting portions of said struts and liftmembers above said levers respectively, each said link in operationbeing under compression.

References Cited in the file of this patent UNITED STATES PATENTS1,652,013 Jones et a1. Dec. 6, 1927 1,733,084 Schmidt Oct. 22, 19291,990,673 Shaughnessy Feb. 12, 1935 2,063,684 Kloos Dec. 8, 19362,229,800 Dean Ian. 28, 1941 2,579,539 Blaire Dec. 25, 1951 2,821,317Locke Jan. 28, 1958 2,857,193 Heppenstall Oct. 21, 1958 FOREIGN PATENTS938,985 Germany Feb. 9, 1956 Attesting Officer UNITED STATES PATENT.OFFICE CERTIFICATE OF CORRECTION Patent No. 3,001,812 September 26 1961I John R. Anderson It is hereby certified that error appears in theabove numbered patent requiring correction and that the said LettersPatent should read as corrected below.

Column 3, line 6 strike out "of"; column 4. line 43,

for "operate" read operative column 6, line 22, for "potrions" readportions column 7, lines 36 and 37 for "sprocket shaft," read sprocketson said sprocket shaft,

Signed and sealed this 6th day of March 1962,

(SEAL) Attest:

ERNEST W. SWIDER DAVID L. LADD Commissioner of Patents

